Telephone receiver



June l 1926.

J. w. DUNGEY TELEPHONE RECEIVER Filed Jan. 2, 1926 PmNANf/vrl. Y a 1464/517250 17464/577250 er nvm/ c T10/v d. ha Ubu-.0

Paienied June i, 192e.

' lastige- .UNITEDeime- ,Peieie einer,

s JOHN WiLLIAM DUNGVEY, 4or`riioiiniiivi,in'oiiooir, ENGLAND@ rnEzLerzielen RECEIVER. p

lApplication IedJanuary 2, 17926*Seria1 No. 78,774, and in Great Britain September 12, i A

'lhisfinvention has reference to telephone receivers of the polarized type lwherein .the`

shell or rear part of the'casing constitutes a permanently magnetized portionpit the e magneticsystem-` This system may comprise one or more cores for receivingl a coil wind? ing or windings. `The shell oriear part has.

secured thereto an iron diaphragm 'in' the usual manner.

ceivers of the character referred to are' ot' improved construction and` enable a` conipara-tively strong and intimate magnetic effeet to-be obtained in the parts .concerned with the result that an improved working y eiiiciency is ensured, the shell or rear part of the casing of the telephone receiver being constituted of `magnetikzable metal and so inagnetized as to comprise two or more iiisuch system may includeas `a partici its circuit a corewhic-h is arrangedin conneccore oft another magnetic system. manner a stronger and more intimate mag iietio eiiect is obtained than hitherto in that magnetic circuits exist between the cores oit adjacent magnetic'systems as well as be` therewith. In thus constructing thev shell -orv iear partei `the. casing .and arranging cores in connection therewith theusual iron dia` phragm of the telephoi'iereceiver ,is sub--` ject to magnetic tension due to each oit the magnetic systems produced, thevibrations oi A, the diaphragm upon'thepassage of electric currents through the? coil windings on the Y cores being correspondingly 'improved with the number of magnetic systems provided; The cores may be of inagnetized metal Aor of soft iron or constituted ot iron wires 'and may be secured to their respectiye parts ot' the shell or rear partei the casing'by any suitable means,vwhile the saidshell or rear part may be pressed out ot sheet metal or may be of cast metal in one piece or constituted of sections. It desir-ed the said shell A:of metal or material of a suitable character. For varying or adjusting the distance betweenthe ends of thecores and the iron dia-n ed` on central portions or pins attached itc the shell 0r rear part or maybe fitted with adf According to v this inventiontelephone re.

y dependent magnet'ie'systems therein. Each" or rear part may be enclosed in an outercase .phragnn the cores maybe adjustably mountustable centre pieces,.tlie adjustment of the cores or centre piecesbei-ng eli'ected preferably `rromthe outside oi the casing.` Alter" natively, the airfgap may ybe *varied as ce sired by adjustment oi' the diaphragm, such.4 i

adjustment being' ellected by the employment oi:- one or more rings within `the-earpiece, the ring or' rings'being preferably .disposed betw'eenthe marginaledge oi the said shell or.`

rear parti andthe diaphragm. Tliediin phragni 'is secured or clamped to the said earpiece', `ortoa cover, trumpetl or equivalent scribed by way of example with reference to Y the `accompanying drawing, in which Figure l is a sectional elevation of atelcphone receiver constructedaccording-to this v` invention.:r .p l p n p Flgufey 2 1S a plan view ot the telephonere' ceivery shewnin Figure 1, with the earpiece- .aiid diaphragm removed. i

.'lthe sliellor rear part f ot the casing coin-` prises magnet systems respectively'existing between the parts ci o, ail and (il b1, the

pole extremities of such portions being approximately positioned according -to si'ijch references and adjacent :poles vbeiifiglot op- .posite polarity, and theparts ci to "7), and y 1 quired and the parts?) to a1 becoming magnetized by induction owing-to its proximity 'to the other magnetic systems. The shell or rear partl f is of the known bell or `cup shape so'l't irjon y'aiid z fittedwith coil windings 4e mid-,respectively secured to thel sheiioi rear part f by screws or rivets at thepoiiits corresponding with the poleextremities Y) and al. rllhe iron diaphragm cv is' arranged4 in contact with theinarginaledges of the shellv or rear part 7 and secured in this posial to `Zi1 being actually 'magnetiaed as jreend, has disposed within it. two cores of.

ti`onbeneath the earpiece CZ by a`screi\`1 threaded ring g engaging with the iiriternallyy screw threaded-'annular flange of the `earpiece. The coil windings e are connected with the iii'sulated'terminals it on rthe shell or rear part `With this `form of oongapA between the said diaphragm and 'the poles,,inagnetio ields being produced be` l tween the poles; and between the latter and n the respective marginal edgesv of the shell or rear part f ot the casing.

lNhat I claim and desire to secure by Letters Patent ot' the United States is l. In a telephonie receiving insti'uinent7 a shell i'itted with a diaphragm, the shell consistingof a plurality ot permanently magnetized portions spaced from one another by a substantial Zone which is not pern'ianently magnetized. y

2. In a telephonie receiving instrument, a rear shell fitted with a diaphragm, said rear shell being in one piece and permanently magnetized with a plurality of magnetic portions therein.

3. In a telephonie receiving instrnnent, an integral cup-shaped rear shell con'iprising a plurality of permanent magnetic portions therein, and va diaphragm disposed in closed proximity to the edge ot the rear shell and subject to the several magnetic portions in the rear shell.

Zl. In a telephonie receiving instrument, a one piece rear shell having a plurality oi f permanent magnetic portions therein, a plu rality ot' cores attached to the rear shell, windings on the said cores, and a diaphragm subject to the magnetic portions of the rear shell and the cores.

5. In a telephone receiver, a cup-shaped permanently magnetized rear shell having a plurality of independent magnets therein,

peripheral portions ot the rear shell being of north and south polarity and intermediate portions ot the rear shell also being oi" north and south polarity, the intermediate portion of north polarity being disposed between the intermediate and peripheral portions of south polarity;

6. A telephone receiver comprising a cupshaped rear shell magnetized to have a plurality of permanent magnets therein with intermediate portions of north polarity between intermediate and peripheral portions of south polarity. cores attached to the rear shell, windings mounted on the cores, Aa diaphragm subject to the magnetic flux of the rear shell and cores, and a periorated cap secured to the periphery of the rear lshell with the diaphragm between the said periphery and thecap.

7. In a telephonie receiving` instrument, a

one piece permanently magnetized rear shell having a plurality ot magnets therein oppositely polarized intermediate portions being alternately disposed relatively to oppositely polarized peripheral portions.

8. In a telephonie receiving instrument, a permanently magnetized rear shell having a plurality of magnets therein, portions ol one polarity being provided between portions of another polarity.

9. In a telephonie receiving instrument, a permanently magnetized part comprising a plurality of magnets therein and having pcripheral portions of north and south polar ity and intermediate portions ot north and south polarity, the intermediate portions ol' north polarity being arranged bet-Ween the peripheral and intermediate portions of south polarity; cores attached to the intermediate portionso't north and south polarity; windings on the said cores; and a diaphragm subject to the plurality 'of magnets and the said cores of opposite polarity.

l0. A telephone receiver comprising a shell having more than one permanent inagnet therein, cores attached to the shell, windings on the cores forming electromagnets of opposite polarity, a diaphragm subject to the magnetic flux of the shell and electromagnets, and a perforated cap secured to the periphery of the shell with the diaphragm between the said periphery and `the cap.

ll. A telephone receiver comprising a one piece permanently magnetized cup-shaped part having a plurality ot' magnets therein opposite peripheral portions of the said part being of north and south polarity and intermediate portions being ot north and south polarity. the intermediate portion or' north polarity being arranged between the peripheral portion of Asouth polarity and the intermediate portion of southy polarity; cores att-ached to the intermediate portions of north and south polarity; windings on the said cores; a diaphragm arranged in connection with the periphery of the said part and lover the said cores, a perforated cap; and means forvsecuring the cap to the said part over the diaphragm.

JOHN WILLIAM DUNGEY. 

